Vehicle seat

Abstract

When a vehicle is rear-ended and a seated user moves rearward in reaction to the rear-end collision, a load generated by a rearward movement of a lumbar portion of the seated user is transmitted from a pressure plate of operating force generating means to an operating force generating mechanism. Then, a pressure roller of the operating force generating mechanism deflects and pulls inner cables of pulling cable devices, thereby moving both end portions of a headrest frame upward. As a result, the headrest frame is moved upward along with headrest supporting brackets smoothly and reliably, whereby a headrest attached to the headrest supporting brackets with headrest stays arranged between the headrest and the respective headrest supporting brackets is moved in the upward-forward direction, that is, toward the head of the seated user smoothly and reliably.

1. A vehicle seat, comprising:
 a seat back frame; 
 headrest supporting brackets which are provided in a center portion of the seat back frame, and to which a headrest is attached; 
 a headrest frame which is supported by the seat back frame at at least two coupling portions such that the headrest is movable in a direction in which the headrest is moved closer to a head of a seated user; 
 an operating force generating device which generates an operating force when receiving a load generated by a rearward movement of the seated user; and 
 an operating force transmitting device which applies the operating force to the at least two coupling portions of the headrest frame in accordance with an operation of the operating force generating device, thereby moving the headrest frame, 
 wherein the operating force transmitting device is formed of paired pulling cable devices, and guide portions that guide the headrest frame in a direction in which the headrest frame is moved are formed in the respective coupling portions, and wherein each of one end portions of outer sheaths of the paired pulling cable devices, the one end portions facing respective end portions of the headrest frame, is positioned on an extension of a line that extends in a direction in which the guide portion guides the headrest frame. 
 
     
     
       2. The vehicle seat according to  claim 1 , wherein the coupling portions are provided at respective end portions of the headrest frame. 
     
     
       3. The vehicle seat according to  claim 1 , wherein a direction in which the headrest frame is moved is an upward direction. 
     
     
       4. The vehicle seat according to  claim 1 , wherein guide portions that guide the headrest frame in a direction in which the headrest frame is moved are formed in the respective coupling portions. 
     
     
       5. The vehicle seat according to  claim 1 , wherein the operating force generated by the operating force generating device is converted into a pulling force by the paired pulling cable devices. 
     
     
       6. The vehicle seat according to  claim 1 , wherein the pulling cable devices are routed such that the pulling cable devices cross each other, and each of the pulling cable devices is arranged in a shape with a gentle curvature. 
     
     
       7. A vehicle seat, comprising:
 a seat back frame; 
 headrest supporting brackets which are provided in a center portion of the seat back frame, and to which a headrest is attached; 
 a headrest frame which is supported by the seat back frame at at least two coupling portions such that the headrest is movable in a direction in which the headrest is moved closer to a head of a seated user; 
 operating force generating means for generating an operating force when receiving the load generated by a rearward movement of the seated user; and 
 operating force transmitting means for applying the operating force to the at least two coupling portions of the headrest frame in accordance with an operation of the operating force generating means, thereby moving the headrest frame, wherein the operating force transmitting means is formed of paired pulling cable means, and guide portions that guide the headrest frame in a direction in which the headrest frame is moved are formed in the respective coupling portions, and wherein each of one end portions of outer sheaths of the paired pulling cable means, the one end portions facing respective end portions of the headrest frame, is positioned on an extension of a line that extends in a direction in which the guide portion guides the headrest frame.